vibrational assignments
Recently Published Documents


TOTAL DOCUMENTS

500
(FIVE YEARS 30)

H-INDEX

42
(FIVE YEARS 2)

2021 ◽  
Vol 23 (09) ◽  
pp. 959-966
Author(s):  
M.B. Bindu ◽  
◽  
Linu Sam ◽  
Amrutha R ◽  
◽  
...  

The PED assignments are analysed for the title molecule. The Force Constants and Reduced masses are presented for reference. Vibrational assignments are made to the title molecule Beta Asarone. .The analysis of Vibrational Assignments is done with an intention to deduce the various properties of Beta Asarone that should aid in analysing the reported toxicity of Beta Asarone.


Author(s):  
Vinayak P. Deshmukh

In this work, density functional theory (DFT) combined with the finite field (FF) method has been adopted to study the molecular structure, vibrational assignments and nonlinear optical (NLO) properties of borazine. The geometrical parameters, vibrational frequencies and NLO properties have been obtained at B3LYP/6-311++G** level of theory. The optimized geometries and vibrational frequencies for borazine are in excellent agreement with the available experimental determinations. The B-N stretching mode observed is the most intense vibrational mode for borazine. The NLO properties of borazine have been investigated by using finite field method. The β and γ values are calculated at field strength of 0.006 a.u. for borazine using different methods and different basis sets.


2021 ◽  
Vol 18 (2) ◽  
pp. 179-189
Author(s):  
Vishnu A. Adole ◽  
Tejendra R. Rajput ◽  
Bapu S. Jagdale

The ethyl 6-amino-5-cyano-2-methyl-4-(4-nitrophenyl)-4H-pyran-3-carboxylate (ACNPPC) was synthesized using an environmentally friendly method and looked into in terms ofstructural, UV-visible, vibrational, and computational analysis. In the gaseous phase, calculations of the density functional theory (DFT) with B3LYP/6-311G(d,p) level were performed. Using Time-dependent density functional theory (TD-DFT) with the B3LYP/6-311G(d,p) basis set method, the HOMO and LUMO energies are calculated. For assessing electrophilic and nucleophilic reactive sites, the molecular electrostatic surface potential (MESP) and contour plot were plotted over the optimized structure. Using computed and experimental vibrational spectra, vibrational assignments were elucidated. To illustrate the charge density in the title compound, Mulliken atomic charges are disclosed. In addition, using vibrational analysis, some thermochemical functions have also been derived. Theoretical simulations have shown the best relationship with experimental results obtained with the B3LYP/6-311G(d,p) level of theory at the DFT and TD-DFT methods.


2021 ◽  
Author(s):  
Marius Ousmanou Bouba ◽  
Fridolin Tchangnwa Nya ◽  
Alhadji Malloum ◽  
Jeanet Conradie ◽  
Jean Marie Ndjaka

Abstract We have investigated the structures, electronic properties, hole and electron mobilities of perfluorinated, perchlorinated and percyanated coronene molecules, using the density functional theory (DFT) at the B3LYP-D3/6-311++G(d,p) and ωB97XD/6-311++G(d,p) levels and Markus-Hush charge transfer theory. The calculated geometric parameters for coronene and perchlorocoronene are in good agreement with the experimental data. Our theoretical investigations have shown B3LYP-D3 functional is suitable to well define vibrational assignments for studied molecules. We have shown that the per-halogenation and per-cyanation of coronene increases the adiabatic electron affinities (AEAs) and reduces the LUMO levels and the hole mobilities thus indicating an ambipolar behavior and air-stable material. We have shown that the percyanation of coronene is a promising pathway for the design of new materials useful in optoelectronics.


2021 ◽  
Vol 27 (7) ◽  
Author(s):  
Wen-Jin Zhang ◽  
Xin Ye ◽  
Ning-Chao Zhang ◽  
Qi-Jun Liu ◽  
Dai-He Fan ◽  
...  

2021 ◽  
Author(s):  
Jeyavijayan Subbiah ◽  
Ramuthai Muthusamy ◽  
Palani Murugan

Abstract The optimized structure, comparative theoretical and experimental vibrational assignments of 2,5-dibromotoluene (DBT) have been evaluated by density functional theory (DFT) with higher basis set calculations. The global reactivity determination such as energy gap, dipole moment has been explored. The locale reactive sites of the molecule are described by applying the electrostatic potential. The interactions between the bonds are assessed by the natural bond orbital (NBO) investigation. The resonance quality 1H and13C (NMR) shifts of the molecule calculated by GIAO method. Optical transparency of the molecule has been analyzed by theoretical UV-Visible spectra. The binding of toluene with serum albumin protein utilizing in silico has been validated and subsequently, the present work clears the method for scheming the drugs in the dealing of serum albumin.


2021 ◽  
Vol 18 (1) ◽  
pp. 86-96
Author(s):  
Rohit S. Shinde

Present investigation deals with the synthesis and density functional theory study (DFT) of a chalcone derivative; (E)-3-(4-chlorophenyl)-1-(4-methoxyphenyl)prop-2-en-1-one (CPMPP). The synthesis of a CPMPP has been carried out by the reaction of 4-methoxyacetophenone and 4-chlorobenzalehyde in ethanol at 30 ℃ under ultrasound irradiation. The structure of a synthesized chalcone is affirmed on the basis of FT-IT, 1H NMR and 13C NMR. The geometry of a CPMPP is optimized by using the density functional theory method at the B3LYP/6-31G(d,p) basis set. The optimized geometrical parameters like bond length and bond angles have been computed. The absorption energies, oscillator strength, and electronic transitions have been derived at the TD-DFT method at the B3LYP/6-31G(d,p) level of theory for B3LYP/6-31G(d p) optimized geometries. The effect of polarity on the absorption energies is discussed by computing UV-visible results in dichloromethane (DCM). Since theoretically obtained wavenumbers are typically higher than experimental wavenumbers, computed wavenumbers were scaled with a scaling factor, and vibrational assignments were made by comparing experimental wavenumbers to scaled theoretical wavenumbers. Quantum chemical parameters have been determined and examined. Molecular electrostatic potential (MEP) surface plot analysis has been carried out at the same level of theory. Mulliken atomic charge study is also discussed in the present study.


2021 ◽  
Author(s):  
Sathya Bangaru ◽  
Prasath Manivannan ◽  
Sivakumar Murugesan ◽  
Govindammal Madhu

Abstract Isorhapontigenin (IRPG) drug emerges as promising efficient inhibitor for H1N1 and H3N2 subtypes which belong to influenza A virus; reported with IC50 value of 35.62 and 63.50 μM respectively. The computed geometrical parameters and vibrational assignments (FT-IR and FT-Raman) are compared with experimental results, these results exhibits good correlation with each other. UV-Vis electronic property reveals that the absorption bands of π→π* transitions, this authorizes that the bands are very strong in the IRPG molecule. The kinetic stability and chemical reactivity of the IRPG molecule was probed through NBO and HOMO-LUMO analysis. Electrophilic and nucleophilic site selectivity of IRPG was explored through MEP map and Fukui function. In molecular docking analysis, the IRPG molecule exhibits the better inhibition constant and binding affinity for H1N1 and H3N2 influenza virus. As a result, the IRPG molecule exposes virtuous biological deeds in nature and it can be performed as a prospective drug candidate for H1N1 and H3N2 viral A influenza.


2021 ◽  
Author(s):  
T. Karthick ◽  
Keshav Kumar Singh ◽  
Swapnil Singh ◽  
Poonam Tandon ◽  
B. Narayana

Abstract In the present study, the isomeric forms of a biologically active 2-Aminopyrimidinium picrate cocrystal were investigated using spectroscopic investigation and Density functional theory (DFT) calculations. The vibrational assignments of IR and Raman peaks were predicted and the experimental IR and Raman spectra of the condensed phase of 2-Aminopyrimidinium picrate were compared with the simulated one. The intrinsic reaction coordinate (IRC) analysis was performed on all the possible reaction pathways to identify the isomeric forms of 2APP and transition state (TS) geometry. From the IRC analysis, a relatively stable form (named as isomer 2) has been identified in addition to the existing isomeric form (isomer 1) in the crystalline packing of 2APP. The presence of non-covalent interactions within the isomeric forms of 2APP was investigated with the help of quantum topological atoms in molecules (QTAIM) analysis. Reactivity descriptors and charge delocalization from lone pair to acceptor entities of both the isomers were predicted to validate the interactions present and to understand the charge distribution within the molecule.


2021 ◽  
Vol 1228 ◽  
pp. 129795
Author(s):  
María V. Castillo ◽  
Maximiliano A. Iramain ◽  
Lilian Davies ◽  
María E. Manzur ◽  
Silvia Antonia Brandán

Sign in / Sign up

Export Citation Format

Share Document